IBM0612404GT3B
IBM0612804GT3B
Advance Rev 0.2
128Mb Double Data Rate Synchronous DRAM
Electrical Characteristics & AC Timing for PC266 - Applicable Specifications
Expressed in Clock Cycles (0 °C ≤ TA ≤ 70 °C; VDDQ = 2.5V ± 0.2V; VDD = 2.5V ± 0.2V, See AC
Characteristics) (Part 2 of 3)
t
= 7.5ns
CK
Symbol
Parameter
Units
Notes
Min
0
Max
t
Write preamble setup time
Write postamble
ns
ns
1-4, 7
1-4, 6
1-4
WPRES
t
3.0
0.25
4.5
WPST
WPRE
t
Write preamble
t
CK
Address and control input hold time
(fast slew rate)
2-4,
11,13,14
t
0.9
0.9
1.0
1.0
ns
ns
ns
ns
IH
Address and control input setup time
(fast slew rate)
2-4,
11,13,14
t
IS
IH
Address and control input hold time
(slow slew rate)
2-4,
12-14
t
Address and control input setup time
(slow slew rate)
2-4,
12-14
t
IS
t
Input pulse width
2.2
6.75
3.0
6
ns
ns
ns
2-4,14
1-4
IPW
t
Read preamble
8.25
4.5
RPRE
t
Read postamble
1-4
RPST
t
Active to Precharge command
Active to Active/Auto-refresh command period
16000
t
1-4
RAS
CK
CK
t
9
t
t
1-4
RC
Auto-refresh to Active/Auto-refresh
command period
t
10
1-4
RFC
RCD
CK
t
Active to Read or Write delay
3
3
3
2
t
t
t
t
1-4
1-4
1-4
1-4
CK
CK
CK
CK
t
Active to Read Command with Autoprecharge
Precharge command period
RAP
t
RP
t
Active bank A to Active bank B command
RRD
1. Input slew rate = 1V/ns
2. The CK/CK input reference level (for timing reference to CK/CK) is the point at which CK and CK cross: the input reference level for
signals other than CK/CK, is V
REF.
3. Inputs are not recognized as valid until V
stabilizes.
REF
4. The Output timing reference level, as measured at the timing reference point indicated in AC Characteristics (Note 3) is V
.
TT
5. t and t transitions occur in the same access time windows as valid data transitions. These parameters are not referred to a
HZ
LZ
specific voltage level, but specify when the device is no longer driving (HZ), or begins driving (LZ).
6. The maximum limit for this parameter is not a device limit. The device operates with a greater value for this parameter, but system
performance (bus turnaround) degrades accordingly.
7. The specific requirement is that DQS be valid (high, low, or some point on a valid transition) on or before this CK edge. A valid tran-
sition is defined as monotonic and meeting the input slew rate specifications of the device. When no writes were previously in
progress on the bus, DQS will be transitioning from Hi-Z to logic low. If a previous write was in progress, DQS could be HIGH, LOW,
or transitioning from high to low at this time, depending on t
.
DQSS
8. A maximum of eight Autorefresh commands can be posted to any given DDR SDRAM device.
9. QFC is enabled as soon as possible after the rising CK edge that registers the Write command.
10. QFC is disabled as soon as possible after the last valid DQS edge transitions Low.
11. For command/address input slew rate ≥ 1.0V/ns. Slew rate is measured between V (AC) and V (AC).
OH
OL
12. For command/address input slew rate ≥ 0.5V/ns and < 1.0V/ns. Slew rate is measured between V (AC) and V (AC).
OH
OL
13. CK/CK slew rates are ≥ 1.0V/ns.
14. These parameters guarantee device timing, but they are not necessarily tested on each device, and they may be guaranteed by
design or tester correlation.
©IBM Corporation. All rights reserved.
Use is further subject to the provisions at the end of this document.
06K0566.F39350
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